1. Field of the Invention
The present invention is generally related to an apparatus for thin-layer cell smear preparation and in-situ hybridization, and more particularly to an apparatus for cell smear preparation and in-situ hybridization to prepare a thin-layer cell smear and carry out in-situ hybridization.
2. Description of the Prior Art
At present, a cervical smear is a major method for cervical cancer prophylaxis. The conventional cervical smear examination uses a cytology spatula or brush to collect cervical cells and coats on a slide for pathological diagnosis in a laboratory. Although the accuracy is not high enough, almost all of the gynecologist-obstetricians agree that the cervical smear examination should be done every year and no problem for three consecutive years can be generally considered as safe from the cervical cancer.
The cervical smear examination has been practiced for years. The controversial point in medicine is that the false negative result is as high as 10˜40%. Some is caused by poor sampling technique while some is caused by the examinee, such as cervical atresia, cervical atrophy without hormone replacement therapy after menopause, and serious anteflexion or retroflexion of uterus, to make sampling difficult.
On the other hand, if the specimen cells on the smear are too thick, that is, many layers of cells are overlapped, the diagnosis becomes difficult. This can be improved by enhancing the training of medical staff.
In addition, the common false negative result is caused by misdiagnosis. Since typically there are two or three hundred thousand cells on a smear, it is difficult to make the diagnosis in a few minutes. Therefore, firstly screening the normal smears by cell technicians is carried out and then the rest of smears, about 10˜20% of smears, are left to be diagnosed by doctors.
In recent years, in order to increase the smear accuracy, many auxiliary screening methods, such as thin-layer cell smear ThinPrep™ and SurePath™, etc., have been developed continually in medicine. In the thin-layer cell smear, a cytology spatula or brush is used to collect cervical cells and placed in a special preservation solution and after stirred to become uniform, the smear with uniform distribution of cells is prepared for observation. The thin-layer smear has uniform distribution of the specimen cells thereon and thus does not cause the phenomenon of cell overlapping so as to increase the detection rate. In addition, cells are concentrated in a relatively small area for easy diagnosis. Therefore, the errors can be reduced and the accuracy is higher than the conventional cervical smear, about 70˜95%.
The factors to cause cervical cancer are numerous. Infection of human papillomaviruses (HPV) is the most important factor. Almost all of the cervical cancers are caused by HPV. U.S. food and drug administration approved in April, 2003 that women with the age over 30 having the cervical smear examination can also choose to have the HPV DNA examination. That is, the cervical specimen cells can be examined to find the existence of HPV DNA, besides abnormal appearance.
In-situ hybridization (ISH) or fluorescence in-situ hybridization (FISH) fixes cells on a slide, destroys cell membranes, and uses a probe under a proper condition to perform hybridization in the cells. The probe uses biotin to label or directly labels fluorescence to have different colors or fluorescence and then a microscope is used to have final diagnosis. Using in-situ hybridization technique to detect HPV dose not require amplification by polymerase chain reaction (PCR). In addition, the pathological staining result and molecular detection reaction can be integrated to provide the individual cell detection result of cells on each smear. Thus, clinicians have further information for diagnosis. Besides detecting virus infection, whether the HPV virus gene inserts into the cell chromatin or not can be recognized. It is an important factor in cytopathic effect.
In the prior art, the in-situ hybridization detection by the thin-layer cell smear has to use the apparatus, that is come together with ThinPrep™ or SurePath™, to prepare the thin-layer cell smear specimen. Then, the device, such as the hybridization frame or hybridization chamber, required to perform the in-situ hybridization experiment is attached on a slide to perform the subsequent reaction, such as hybridization. These operations are tedious and the labor and material costs are high.